While GPS is good for tracking objects on the surface, once an object goes underground it makes it much harder to find. In the wake of the July 7th (2005) London underground attacks, UK emergency services have been looking for a way to be able to find people who may be trapped underground or under debris and this ‘badger-tracking system’ may provide the answer.

To get around this problem, the duo developed a technology based on generating very low-frequency fields that are capable of penetrating obstacles, enabling positioning and communication even through thick layers of rock, soil, and concrete. Of course, there is the problem that low-frequency fields can vanish very quickly, but the team hopes to overcome this with clever signal-processing algorithms.

“Most technologies are only checking the magnitude of the signal – the signal strength from each transmitter – to work out distance,” Andrew Markham said in an interview to Wired.co.uk. “In contrast the new technology measures ‘vectors, which give you the magnitude and direction… Our technology can work out your position in three dimensions from a single transmitter.”

Of course the team also realizes the real-world benefits apart from tracking badgers. Working with Isis Innovation, they have been adapting the technology for a multitude of purposes in addition to search and rescue, including location-based advertising and tracking people and equipment in modern mines.